1. Field
At least one example embodiment relates to a tunable photonic crystal color filter and/or a color image display apparatus including the same.
2. Description of the Related Art
A color image display apparatus generally includes an image panel that displays a gray scale of an image and a color filter that displays a color of the image.
A reflection type color image display apparatus displays colors by dividing an area of each of the pixels that constitute an image into three fixed colors and transmitting or reflecting light from the color area. In such area-divided color filters, when a primary color or a color approximating the primary color is displayed, light that is transmitted from the remaining color areas is fully blocked resulting in a large amount of color loss.
In addition, absorption type color filters that are generally used in a color image display apparatus transmit light only to a desired color area and absorb light from the remaining color areas. Thus, loss of light that occurs when light is transmitted via an absorption color filter is large in the color image display apparatus. Also, when an absorption type color filter is used in a reflection type color image display apparatus, due to characteristics of the reflection type color image panels, light passes through the absorption type color filter twice, and thus, loss of light in the absorption type color filter doubles. Accordingly, it is more difficult to display a bright color.
Thus, as an alternative to absorption type color filters, color filters using a photonic crystal whereby light is fully reflected from a color area corresponding to a photonic band gap and light in the remaining color areas is transmitted have been studied.